Lamp base



FIG. 1 is a perspective view thereof;

FIG. 2 is a front view thereof;

FIG. 3 is a back view thereof;

FIG. 4 is a right side view thereof;

FIG. 5 is a left side view thereof;

FIG. 6 is a top view thereof;

FIG. 7 is a bottom view thereof; and,

FIG. 8 is a perspective view showing a lamp base and lamp shade withtube, shown in dotted line, for illustrative purpose only.

The ornamental design for a lamp base, as shown and described.